What is the ampacity of each 6 AWG THW copper conductor when there are four in a nipple?

The ampacity of a conductor refers to the maximum amount of electrical current it can carry before overheating. For a 6 AWG THW copper conductor, the baseline ampacity is typically 65 amperes when considering standard conditions. However, the actual amount may depend on various factors such as the number of conductors in a raceway (or nipple, in this case), which can lead to adjustments due to derating.

When four 6 AWG THW copper conductors are grouped together in a nipple, there’s a need to apply a derating factor due to the increased heat that results from multiple conductors being installed in confined spaces. Typically, more than three conductors in a raceway necessitates a 80% derating factor.

Under the original 65 ampacity for 6 AWG copper, applying the derating factor when there are four conductors would reduce the ampacity effectively. Since the original awg safety rating allows 65 amperes under single conductor conditions, it can be concluded that despite the presence of four conductors, the ampacity remains at 65 amperes for each individual conductor as long as derating conditions are not reached.

This understanding bridges the gap between theoretical calculations and practical applications in electrical